The present invention relates generally to surgical tools and methods. More particularly, the present invention relates to a bipolar cauterizing and cutting tool for use with robotic surgical systems.
A significant number of different surgical instruments are used during each surgical procedure. In minimally invasive or robotic surgical procedures, the number of entry ports into a patient is generally limited because of space constraints, as well as the desire to avoid unnecessary incisions in the patient. Hence, a number of different surgical instruments will typically be introduced through the same trocar sleeve into the abdomen during, for example, laparoscopic procedures. As a result, the number of surgical instruments will often be attached and detached from a single instrument holder of a manipulator during an operation. Since each instrument change lengthens the surgical procedure and increases the patient's risk, it is beneficial to make a minimal amount of instrument changes during the surgical procedure.
Electrosurgery refers broadly to a class of medical procedures which rely on the application of high frequency electrical energy, usually radio frequency energy, to patient tissue to achieve a number of possible effects, such as cutting, coagulation, necrosis, and the like. Of particular interest to the present invention, bipolar electrosurgical procedures rely on contacting electrodes of different polarity in close proximity to each other against or into tissue. For example, in some minimally invasive and robotically controlled surgical procedures, tissue in the patient's body must be cauterized and severed. To perform such a procedure, bipolar or monopolar cauterizing grips can be introduced through the trocar to engage the target tissue. An electrical energy, such as radiofrequency energy, is delivered to the grips to cauterize the engaged tissue. Unfortunately, conventional cauterizing grips are insufficient to cut the cauterized tissue because they generally use the entire two grips as the two electrodes. The grips are designed primarily to grasp tissue and have a large surface area. The large surface area translates into a small power density and mkes them more effective as widespread heating (i.e. the size of the grips and some peripheral thermal damage to the surrounding tissue). Unfortunately, the heating does not concentrate the energy enough to allow for cutting of the gripped tissue. Thus, to achieve cutting of the cauterized tissue, a separate cutting instrument can be introduced into the body cavity through the trocar. However, the time associated with disconnecting the cauterizing grips from the body and connecting the cutting instrument to the robotic arm unnecessarily lengthens the surgical procedure and increases the risk to the patient.
One possible method of improving cauterizing and cutting with a robotic surgical system is to integrate a cutting element with the cauterizing grips. Unfortunately, because of the small size of the trocar and surgical instruments, it is difficult to integrate a cutting element with the cauterizing grips. Moreover, the incorporation of the cutting element in the grips is difficult because of the space available, especially with offset electrodes when trying to maintain a slim profile for good visualization.
In light of the above, it would be desirable to provide improved robotic surgery tools, systems, and method. It would further be desirable to provide a bipolar tool that can cauterize and cut tissue. It would be especially desirable if these enhanced robotic tools and techniques resulted in further improvement in the safety and reliability of the robotic surgical systems.